The purpose of this study is to determine the effects of shift work and length of shift on health-related behaviors such as sleeping, eating, and physical activity. This study will involve 524 public safety dispatchers; those who answer emergency calls for assistance and dispatch the appropriate form of aid. The dispatchers will be recruited from the 363 primary Public Safety Answering Points (PSAPs) throughout California. The data will be collected in two stages using telephone interviews. The first stage will involve interviewing PSAP directors to obtain information regarding the working conditions and the number of dispatchers employed at their center, and to obtain their consent to have the dispatchers at their center participate in the second stage of the study. The second stage of the study involves the use of a 20 minute telephone interview to collect information from the dispatchers regarding their eating, sleeping, and physical activity behaviors during a typical work and non-work day, during their current shift. Outcome measures include percentage of total calories from fat, MET (a measure of energy expenditure), and number of hours of sleep in a 24-hour period. Two sample "t tests" will be used to test for significant difference between day and shift workers. The day and shift workers will be divided into those who work 8.5 hours per day and those who work > 8.5 hours per day. This will allow for comparisons between day and shift workers within and across 8 and 12 hour schedules. A one-way ANOVA will be used to test for significant differences between groups. Public safety dispatchers are a unique group, in that the majority are female and they perform a high stress sedentary task. Therefore, the information learned from this study will make an important contribution to the literature concerning the health effects of shift work.